Introduction This blog post describes how to measure reflection and transmission coefficients using the Zurich Instruments UHFLI Lock-in Amplifier and a directional coupler. Network analysis is commonly performed in radiofrequency (RF) measurements. A network analyzer is an instrument that measures the network parameters of electrical circuits. Circuits that can be...
When a sinusoidal waveform is periodically modulated in either amplitude or frequency, sidebands are generated as a result of this carrier modulation. These sidebands can be measured using a lock-in amplifier. Zurich Instruments' lock-in amplifiers (such as the HF2LI and the UHFLI) can measure up to 8 frequencies simultaneously and...
Ground loops can pose a serious problem in many measurement setups. Due to the multiple connections to and from the HF2TA Current Amplifier and other external components, several ground loop related issues can pop up in the signal being measured. These issues can be high-frequency oscillations (> 10 MHz), 50/60...
With the miniaturization of circuits and components such as MEMS and now also NEMS, the variety and quality of macro-fabricated devices have dramatically increased, leading to packaged or embedded systems with particularly sensitive electromechanical properties. The basic properties, such as resonance frequencies, Q-factor and dissipative power requires more and more...
Every now and then, a differential amplifier in the frequency range of the UHFLI Lock-in Amplifier is needed. The requirements for such an amplifier are low noise and a frequency range of at least 600 MHz. A commercial solution with an active differential amplifier is not available today. A straightforward...
Double-sideband suppressed-carrier (DSB-SC) modulation is an amplitude modulation that consists only of the two symmetrical sidebands and no carrier band. I came across this scheme in an ultrasound application, where power utilization can be maximized when all power is available on the sidebands. It turns out that DSB-SC modulation can...
Phase-synchronous operation of a variety of frequency sources and analyzers is a common requirement, which is usually solved by distributing a 10 MHz clock signal to which the individual instruments are phase-locked. This ensures not only a perfect frequency match between the referenced instruments, but also guarantees a constant phase...
Following my previous blog post , people advised me to try to broadcast FM radio too. For this, I had to retreat into Zurich Instruments' shielded radiation lab, so that my experiment would remain concealed. It then took about 5 minutes to broadcast tunes from my mobile phone's 3.5 mm...
Someone at Zurich Instruments soldered a 3.5-mm headphone socket to a BNC cable and attached a 75-cm antenna wire to the Signal Input of the UHFLI Lock-in Amplifier with the UHF-PID PID/PLL option and was happily listening to FM radio. Abuse alert! I instantly had to copy that one.
Using a Zurich Instruments lock-in amplifier, you can measure the quality factor of an arbitrary resonator - typically a resonant beam used in non-contact atomic force microscopy (NC-AFM) applications. This can be useful to increase phase sensitivity in a phase-locked loop (PLL) setup, for example, or to increase the characteristic...
